Business planning by county

Illinois county reference

102 counties and county equivalents in Illinois. Search names or FIPS codes, compare Census geography and keep the original sources with your work.

• Adams County

  Illinois · FIPS 17001

  64,267 residents · 2025 estimate

• Alexander County

  Illinois · FIPS 17003

  4,570 residents · 2025 estimate

• Bond County

  Illinois · FIPS 17005

  16,959 residents · 2025 estimate

• Boone County

  Illinois · FIPS 17007

  53,568 residents · 2025 estimate

• Brown County

  Illinois · FIPS 17009

  6,401 residents · 2025 estimate

• Bureau County

  Illinois · FIPS 17011

  32,510 residents · 2025 estimate

• Calhoun County

  Illinois · FIPS 17013

  4,300 residents · 2025 estimate

• Carroll County

  Illinois · FIPS 17015

  15,419 residents · 2025 estimate

• Cass County

  Illinois · FIPS 17017

  12,463 residents · 2025 estimate

• Champaign County

  Illinois · FIPS 17019

  209,972 residents · 2025 estimate

• Christian County

  Illinois · FIPS 17021

  33,443 residents · 2025 estimate

• Clark County

  Illinois · FIPS 17023

  15,114 residents · 2025 estimate

• Clay County

  Illinois · FIPS 17025

  12,793 residents · 2025 estimate

• Clinton County

  Illinois · FIPS 17027

  37,128 residents · 2025 estimate

• Coles County

  Illinois · FIPS 17029

  46,607 residents · 2025 estimate

• Cook County

  Illinois · FIPS 17031

  5,194,625 residents · 2025 estimate

• Crawford County

  Illinois · FIPS 17033

  18,648 residents · 2025 estimate

• Cumberland County

  Illinois · FIPS 17035

  10,208 residents · 2025 estimate

• De Witt County

  Illinois · FIPS 17039

  15,118 residents · 2025 estimate

• DeKalb County

  Illinois · FIPS 17037

  101,835 residents · 2025 estimate

• Douglas County

  Illinois · FIPS 17041

  19,880 residents · 2025 estimate

• DuPage County

  Illinois · FIPS 17043

  934,298 residents · 2025 estimate

• Edgar County

  Illinois · FIPS 17045

  16,323 residents · 2025 estimate

• Edwards County

  Illinois · FIPS 17047

  5,898 residents · 2025 estimate

• Effingham County

  Illinois · FIPS 17049

  34,519 residents · 2025 estimate

• Fayette County

  Illinois · FIPS 17051

  20,790 residents · 2025 estimate

• Ford County

  Illinois · FIPS 17053

  13,216 residents · 2025 estimate

• Franklin County

  Illinois · FIPS 17055

  36,916 residents · 2025 estimate

• Fulton County

  Illinois · FIPS 17057

  32,901 residents · 2025 estimate

• Gallatin County

  Illinois · FIPS 17059

  4,616 residents · 2025 estimate

• Greene County

  Illinois · FIPS 17061

  11,313 residents · 2025 estimate

• Grundy County

  Illinois · FIPS 17063

  54,052 residents · 2025 estimate

• Hamilton County

  Illinois · FIPS 17065

  7,859 residents · 2025 estimate

• Hancock County

  Illinois · FIPS 17067

  16,803 residents · 2025 estimate

• Hardin County

  Illinois · FIPS 17069

  3,588 residents · 2025 estimate

• Henderson County

  Illinois · FIPS 17071

  5,984 residents · 2025 estimate

• Henry County

  Illinois · FIPS 17073

  48,095 residents · 2025 estimate

• Iroquois County

  Illinois · FIPS 17075

  26,150 residents · 2025 estimate

• Jackson County

  Illinois · FIPS 17077

  52,501 residents · 2025 estimate

• Jasper County

  Illinois · FIPS 17079

  9,032 residents · 2025 estimate

• Jefferson County

  Illinois · FIPS 17081

  36,147 residents · 2025 estimate

• Jersey County

  Illinois · FIPS 17083

  21,160 residents · 2025 estimate

• Jo Daviess County

  Illinois · FIPS 17085

  21,594 residents · 2025 estimate

• Johnson County

  Illinois · FIPS 17087

  13,363 residents · 2025 estimate

• Kane County

  Illinois · FIPS 17089

  525,757 residents · 2025 estimate

• Kankakee County

  Illinois · FIPS 17091

  105,525 residents · 2025 estimate

• Kendall County

  Illinois · FIPS 17093

  145,470 residents · 2025 estimate

• Knox County

  Illinois · FIPS 17095

  47,767 residents · 2025 estimate

• Lake County

  Illinois · FIPS 17097

  719,339 residents · 2025 estimate

• LaSalle County

  Illinois · FIPS 17099

  107,773 residents · 2025 estimate

• Lawrence County

  Illinois · FIPS 17101

  13,790 residents · 2025 estimate

• Lee County

  Illinois · FIPS 17103

  32,914 residents · 2025 estimate

• Livingston County

  Illinois · FIPS 17105

  35,057 residents · 2025 estimate

• Logan County

  Illinois · FIPS 17107

  27,182 residents · 2025 estimate

• Macon County

  Illinois · FIPS 17115

  99,300 residents · 2025 estimate

• Macoupin County

  Illinois · FIPS 17117

  43,748 residents · 2025 estimate

• Madison County

  Illinois · FIPS 17119

  263,110 residents · 2025 estimate

• Marion County

  Illinois · FIPS 17121

  36,382 residents · 2025 estimate

• Marshall County

  Illinois · FIPS 17123

  11,473 residents · 2025 estimate

• Mason County

  Illinois · FIPS 17125

  12,411 residents · 2025 estimate

• Massac County

  Illinois · FIPS 17127

  13,502 residents · 2025 estimate

• McDonough County

  Illinois · FIPS 17109

  25,916 residents · 2025 estimate

• McHenry County

  Illinois · FIPS 17111

  317,751 residents · 2025 estimate

• McLean County

  Illinois · FIPS 17113

  171,419 residents · 2025 estimate

• Menard County

  Illinois · FIPS 17129

  11,863 residents · 2025 estimate

• Mercer County

  Illinois · FIPS 17131

  15,229 residents · 2025 estimate

• Monroe County

  Illinois · FIPS 17133

  34,840 residents · 2025 estimate

• Montgomery County

  Illinois · FIPS 17135

  28,076 residents · 2025 estimate

• Morgan County

  Illinois · FIPS 17137

  32,515 residents · 2025 estimate

• Moultrie County

  Illinois · FIPS 17139

  14,371 residents · 2025 estimate

• Ogle County

  Illinois · FIPS 17141

  51,399 residents · 2025 estimate

• Peoria County

  Illinois · FIPS 17143

  178,553 residents · 2025 estimate

• Perry County

  Illinois · FIPS 17145

  20,160 residents · 2025 estimate

• Piatt County

  Illinois · FIPS 17147

  16,791 residents · 2025 estimate

• Pike County

  Illinois · FIPS 17149

  14,231 residents · 2025 estimate

• Pope County

  Illinois · FIPS 17151

  3,672 residents · 2025 estimate

• Pulaski County

  Illinois · FIPS 17153

  4,820 residents · 2025 estimate

• Putnam County

  Illinois · FIPS 17155

  5,619 residents · 2025 estimate

• Randolph County

  Illinois · FIPS 17157

  29,921 residents · 2025 estimate

• Richland County

  Illinois · FIPS 17159

  15,219 residents · 2025 estimate

• Rock Island County

  Illinois · FIPS 17161

  141,869 residents · 2025 estimate

• Saline County

  Illinois · FIPS 17165

  22,772 residents · 2025 estimate

• Sangamon County

  Illinois · FIPS 17167

  194,170 residents · 2025 estimate

• Schuyler County

  Illinois · FIPS 17169

  6,657 residents · 2025 estimate

• Scott County

  Illinois · FIPS 17171

  4,866 residents · 2025 estimate

• Shelby County

  Illinois · FIPS 17173

  20,576 residents · 2025 estimate

• St. Clair County

  Illinois · FIPS 17163

  250,708 residents · 2025 estimate

• Stark County

  Illinois · FIPS 17175

  5,319 residents · 2025 estimate

• Stephenson County

  Illinois · FIPS 17177

  43,220 residents · 2025 estimate

• Tazewell County

  Illinois · FIPS 17179

  130,049 residents · 2025 estimate

• Union County

  Illinois · FIPS 17181

  16,656 residents · 2025 estimate

• Vermilion County

  Illinois · FIPS 17183

  71,259 residents · 2025 estimate

• Wabash County

  Illinois · FIPS 17185

  10,907 residents · 2025 estimate

• Warren County

  Illinois · FIPS 17187

  16,222 residents · 2025 estimate

• Washington County

  Illinois · FIPS 17189

  13,564 residents · 2025 estimate

• Wayne County

  Illinois · FIPS 17191

  15,882 residents · 2025 estimate

• White County

  Illinois · FIPS 17193

  13,250 residents · 2025 estimate

• Whiteside County

  Illinois · FIPS 17195

  54,121 residents · 2025 estimate

• Will County

  Illinois · FIPS 17197

  712,253 residents · 2025 estimate

• Williamson County

  Illinois · FIPS 17199

  67,225 residents · 2025 estimate

• Winnebago County

  Illinois · FIPS 17201

  283,674 residents · 2025 estimate

• Woodford County

  Illinois · FIPS 17203

  38,111 residents · 2025 estimate

Use the county data

Use a county reference when organizing a market-research brief, outreach territory or business calculation. County population gives geographic context; it does not measure the number of qualified customers.

These are geographic reference records, not contact lists or verified sales leads.

Geography: 2025 U.S. Census Gazetteer. Population: Vintage 2025 estimates, July 1, 2025. County equivalents include parishes, boroughs, independent cities and planning regions. Puerto Rico population is not supplied by this population file.